Q: Can a rootkit be used for a good purpose, or is it always classified as malware?

A:
The term rootkit was developed as a hacker term, although rootkits can also be used for what some vendors consider valid purposes. For example, if Digital Rights Management (DRM) software is installed and kept hidden, it can control the use of licensed, copyrighted material and prevent the user from removing the hidden enforcement program. However, such usage is no more welcomed than a rootkit that does damage or allows spyware to thrive without detection.

Q: I have an infected system and I cannot figure out what is wrong. Where can I look to find further information on the Internet?

A:
Information about specific viruses and instructions on how to clean an infected system is available at www.symantec.com and www.mcafee.com. Both antivirus vendors provide detailed databases that list and describe known viruses. For more information on viruses, worms, and Trojans, see the article How Computer Viruses Work, at www.howstuffworks.com/virus.htm.

Q: What are cookies and spyware? How are they different? Do some Web sites use cookies to exploit user information?

A:
A cookie is just a bit of text in a file on your computer, containing a small amount of information that identifies you to a particular Web site, and whatever information that site wanted to retain about you when you were visiting. Cookies are a legitimate tool that many Web sites use to track visitor information. .

For example, you might go to an online computer store and place an item in your basket, but decide not to buy it right away because you want to compare prices. The store can choose to put the information about what products you put into your basket in a cookie stored on your computer. This is an example of a good use of cookies to help the user experience. The only Web sites that are supposed to be able to retrieve the information stored in a cookie are the Web sites that wrote the information in that particular cookie.

This should ensure your privacy by stopping any site other than the one you are visiting from being able to read any cookies left by that site. Some Web sites do use cookies to exploit user information, however. Some also may deceive users or omit their policies.

For example, they may track your Web surfing habits across many different Web sites without informing you, and then use this data to customize the advertisements you see on Web sites, which typically is considered an invasion of privacy. It is difficult to identify this and other forms of cookie abuse, which makes it difficult to decide whether, when, and how to block them from your system. In addition, the acceptable level of shared information varies among users, so it is difficult to create an anticookie program to meet everyones needs.